Expose 'subscribed' for epics in GraphQL

Exposes subscribed attribute for epics in GraphQL

doc/api/graphql/reference/index.md

@@ -211,6 +211,7 @@ The API can be explored interactively using the [GraphiQL IDE](../index.md#graph
 | `relativePosition` | Int | The relative position of the epic in the Epic tree |
 | `relationPath` | String |  |
 | `reference` | String! |  |
+| `subscribed` | Boolean! | Boolean flag for whether the currently logged in user is subscribed to this epic |
 
 ### EpicIssue
 

ee/app/graphql/types/epic_type.rb

@@ -58,6 +58,12 @@ module Types
       argument :full, GraphQL::BOOLEAN_TYPE, required: false, default_value: false # rubocop:disable Graphql/Descriptions
     end
 
+    field :subscribed, GraphQL::BOOLEAN_TYPE,
+      method: :subscribed?,
+      null: false,
+      complexity: 5,
+      description: 'Boolean flag for whether the currently logged in user is subscribed to this epic'
+
     field :issues, # rubocop:disable Graphql/Descriptions
           Types::EpicIssueType.connection_type,
           null: true,

ee/app/presenters/epic_presenter.rb

@@ -35,13 +35,17 @@ class EpicPresenter < Gitlab::View::Presenter::Delegated
     end
   end
 
+  def subscribed?
+    epic.subscribed?(current_user)
+  end
+
   private
 
   def initial_data
     {
       labels: epic.labels,
       participants: participants,
-      subscribed: epic.subscribed?(current_user)
+      subscribed: subscribed?
     }
   end
 

ee/changelogs/unreleased/issue_31913.yml

+---
+title: Expose subscribed attribute for Epics in GraphQL
+merge_request: 18607
+author:
+type: added

ee/spec/graphql/types/epic_type_spec.rb

@@ -10,7 +10,7 @@ describe GitlabSchema.types['Epic'] do
       due_date due_date_is_fixed due_date_fixed due_date_from_milestones
       closed_at created_at updated_at children has_children has_issues
       web_path web_url relation_path reference issues
-      user_permissions notes discussions relative_position
+      user_permissions notes discussions relative_position subscribed
     ]
   end
 
@@ -21,4 +21,6 @@ describe GitlabSchema.types['Epic'] do
   it { expect(described_class).to require_graphql_authorizations(:read_epic) }
 
   it { expect(described_class).to have_graphql_fields(fields) }
+
+  it { is_expected.to have_graphql_field(:subscribed, complexity: 5) }
 end

spec/graphql/types/notes/diff_position_type_spec.rb

@@ -7,6 +7,6 @@ describe GitlabSchema.types['DiffPosition'] do
                        :new_path, :position_type, :old_line, :new_line, :x, :y,
                        :width, :height]
 
-    is_expected.to have_graphql_field(*expected_fields)
+    is_expected.to have_graphql_fields(*expected_fields)
   end
 end

spec/support/matchers/graphql_matchers.rb

@@ -28,9 +28,15 @@ RSpec::Matchers.define :have_graphql_fields do |*expected|
   end
 end
 
-RSpec::Matchers.define :have_graphql_field do |field_name|
+RSpec::Matchers.define :have_graphql_field do |field_name, args = {}|
   match do |kls|
-    expect(kls.fields.keys).to include(GraphqlHelpers.fieldnamerize(field_name))
+    field = kls.fields[GraphqlHelpers.fieldnamerize(field_name)]
+
+    expect(field).to be_present
+
+    args.each do |argument, value|
+      expect(field.send(argument)).to eq(value)
+    end
   end
 end